Design and Parameters Analysis of a Solar Powered UAV for Extended Endurance

This paper presents a conceptual design methodology for solar-powered range-extending unmanned aerial vehicles (UAVs) based on the solar-powered range-extending coefficient. Solar-powered range-extending UAVs are primarily designed for daytime flight. The design methodology is based on energy and mass balance during level flight. Based on the Keidel solar irradiance model, the solar cell model, the maximum power point tracker (MPPT) model and lithium battery model, a simplified model for energy acquisition and storage is developed for the UAV. The factors influencing the solar-powered range-extending coefficient are analyzed by deriving the energy balance. The impact of the solar-powered range-extending coefficient, endurance time, and other key parameters on the overall parameters of the UAV such as cruise speed, wing load and payload coefficient is discussed. To verify the method, a hand-launchable UAV with a wingspan of 3.2 m was designed and constructed. Flight tests demonstrate that the UAV can sustain over 8 h of flight time in ecological monitoring tasks.